The elongation factor 1-alpha as storage reserve and environmental sensor in Nicotiana tabacum L. seeds

Given their critical role in plant reproduction and survival, seeds demand meticulous regulatory mechanisms to effectively store and mobilize reserves. Within seeds, the condition of storage reserves heavily depends on environmental stimuli and hormonal activation. Unlike non-protein reserves that commonly employ dedicated regulatory proteins for signaling, proteinaceous reserves may show a unique form of 'self-regulation', amplifying efficiency and precision in this process. Proteins rely on stability to carry out their functions. However, in specific physiological contexts, particularly in seed germination, protein instability becomes essential, fulfilling roles from signaling to regulation. In this study, the elongation factor 1-alpha has been identified as a main proteinaceous reserve in Nicotiana tabacum L. seeds and showed peculiar changes in stability based on tested chemical and physical conditions. A detailed biochemical analysis followed these steps to enhance our understanding of these protein attributes. The protein varied its behavior under different conditions of pH, temperature, and salt concentration, exhibiting shifts within physiological ranges. Notably, distinct solubility transitions were observed, with the elongation factor 1-alpha becoming insoluble upon reaching specific thresholds determined by the tested chemical and physical conditions. The findings are discussed within the context of seed signaling in response to environmental conditions during the key transitions of dormancy and germination

Profiles of VGF peptides in the rat brain and their modulations after Phencyclidine treatment

From the VGF precursor protein originate several low molecular weight peptides, whose distribution in the brain and blood circulation is not entirely known. Among the VGF peptides, those containing the N-terminus portion were altered in the cerebro-spinal fluid (CSF) and hypothalamus of schizophrenia patients. "Hence, we aimed to better investigate the involvement of the VGF peptides in schizophrenia by studying their localization in the brain regions relevant for the disease, and revealing their possible modulations in response to certain neuronal alterations occurring in schizophrenia". We produced antibodies against different VGF peptides encompassing the N-terminus, but also C-terminus-, TLQP-, GGGE- peptide sequences, and the so named NERP-3 and -4. These antibodies were used to carry out specific ELISA and immunolocalization studies while mass spectrometry (MS) analysis was also performed to recognize the intact brain VGF fragments. We used a schizophrenia rat model, in which alterations in the prepulse inhibition (PPI) of the acoustic startle response occurred after PCP treatment. In normal rats, all the VGF peptides studied were distributed in the brain areas examined including hypothalamus, prefrontal cortex, hippocampus, accumbens and amygdaloid nuclei and also in the plasma. By liquid chromatography-high resolution mass, we identified different intact VGF peptide fragments, including those encompassing the N-terminus and the NERPs. PCP treatment caused behavioral changes that closely mimic schizophrenia, estimated by us as a disruption of PPI of the acoustic startle response. The PCP treatment also induced selective changes in the VGF peptide levels within certain brain areas. Indeed, an increase in VGF C-terminus and TLQP peptides was revealed in the prefrontal cortex (p < 0.01) where they were localized within parvoalbumin and tyrosine hydroxylase (TH) containing neurons, respectively. Conversely, in the nucleus accumbens, PCP treatment produced a down-regulation in the levels of VGF C-terminus-, N-terminus- and GGGE- peptides (p < 0.01), expressed in GABAergic- (C-terminus/GGGE) and somatostatin- (N-terminus) neurons. These results confirm that VGF peptides are widely distributed in the brain and modulated in specific areas involved in schizophreni

Biodiversity of Sardinian marine caves: sponge fauna = Biodiversità delle grotte marine della Sardegna: la fauna a poriferi

This paper focuses on a faunistic study on sponges from three submerged caves of the Marine Protected Area of Capo Caccia-Isola Piana. Results contribute to the assessment of biodiversity of the scarcely known Sardinian Sea

Different Thymosin Beta 4 Immunoreactivity in Foetal and Adult Gastrointestinal Tract

Background: Thymosin beta 4 (T beta(4)) is a member of beta-thymosins, a family of peptides that play essential roles in many cellular functions. A recent study from our group suggested a role for T beta(4) in the development of human salivary glands. The aim of this study was to analyze the expression of T beta(4) in the human gut during development, and in the adult. Methodology/Principal Findings: Immunolocalization of T beta(4) was studied in autoptic samples of tongue, oesophagus, stomach, ileum, colon, liver and pancreas obtained from two human foetuses and two adults. T beta(4) appeared unevenly distributed, with marked differences between foetuses and adults. In the stomach, superficial epithelium was positive in foetuses and negative in adults. Ileal enterocytes were strongly positive in the adult and weakly positive in the foetuses. An increase in reactivity for T beta(4) was observed in superficial colon epithelium of adults as compared with the foetuses. Striking differences were found between foetal and adult liver: the former showed a very low reactivity for T beta(4) while in the adult we observed a strong reactivity in the vast majority of the hepatocytes. A peculiar pattern was found in the pancreas, with the strongest reactivity observed in foetal and adult islet cells. Significance: Our data show a strong expression of T beta(4) in the human gut and in endocrine pancreas during development. The observed differential expression of T beta(4) suggests specific roles of the peptide in the gut of foetuses and adults. The observed heterogeneity of T beta(4) expression in the foetal life, ranging from a very rare detection in liver cells up to a diffuse reactivity in endocrine pancreas, should be taken into account when the role of T beta(4) in the development of human embryo is assessed. Future studies are needed to shed light on the link between T beta(4) and organogenesis

Planarians of temporary waters (Platyhelminthes tricladida)

Freshwater planarians are fragile animals susceptible to desiccation and high temperature and characterized by a poor dispersal power requiring contiguous freshwaters to survive and disperse. They are indeed excellent biogeographic models. However, some species of Planariidae (genera Phagocata and Hymanella) and Dugesiidae (genus Spathula) are known inhabiting temporary waters particularly from the Nearctic, Palaearctic and Australasian regions

How to survive and persist in ephemeral water bodies?: the case of sponges (Porifera: Spongillina)

Ephemeral water bodies are subjected to unforeseeable and extreme fluctuations of environmental conditions constraining biodiversity values. Although data are fragmentary and scattered in the literature sponges are known to be able to colonize temporary/intermittent water bodies

Modificazioni semisintetiche dell'olio essenziale di <i>Myrtus communis</i> L. vegetante spontaneo in Sardegna e valutazione dell'attività antimicrobica

Il Myrtus communis, in Sardegna, e non solo, ha sempre rivestito un ruolo importante sia nel campo liquoristico alimentare che anche per le sue proprietà medicamentose. In questo lavoro è stato studiato l’olio essenziale di questa pianta, prendendolo come prodotto di partenza per effettuare delle modificazioni chimiche sulla componente terpenica portando alla formazione di specifici gruppi funzionali

Characterization of Cystatin B Interactome in Saliva from Healthy Elderly and Alzheimer's Disease Patients

Cystatin B is a small, multifunctional protein involved in the regulation of inflammation, innate immune response, and neuronal protection and found highly abundant in the brains of patients with Alzheimer's disease (AD). Recently, our study demonstrated a significant association between the level of salivary cystatin B and AD. Since the protein is able to establish protein-protein interaction (PPI) in different contexts and aggregation-prone proteins and the PPI networks are relevant for AD pathogenesis, and due to the relevance of finding new AD markers in peripheral biofluids, we thought it was interesting to study the possible involvement of cystatin B in PPIs in saliva and to evaluate differences and similarities between AD and age-matched elderly healthy controls (HC). For this purpose, we applied a co-immunoprecipitation procedure and a bottom-up proteomics analysis to purify, identify, and quantify cystatin B interactors. Results demonstrated for the first time the existence of a salivary cystatin B-linked multi-protein complex composed by 82 interactors and largely expressed in the body. Interactors are involved in neutrophil activation, antimicrobial activity, modulation of the cytoskeleton and extra-cellular matrix (ECM), and glucose metabolism. Preliminary quantitative data showed significantly lower levels of triosophosphate isomerase 1 and higher levels of mucin 7, BPI, and matrix Gla protein in AD with respect to HC, suggesting implications associated with AD of altered glucose metabolism, antibacterial activities, and calcification-associated processes. Data are available via ProteomeXchange with identifiers PXD039286 and PXD030679

Combined Salivary Proteome Profiling and Machine Learning Analysis Provides Insight into Molecular Signature for Autoimmune Liver Diseases Classification

Autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) are autoimmune liver diseases that target the liver and have a wide spectrum of presentation. A global overview of quantitative variations on the salivary proteome in presence of these two pathologies is investigated in this study. The acid-insoluble salivary fraction of AIH and PBC patients, and healthy controls (HCs), was analyzed using a gel-based bottom-up proteomic approach combined with a robust machine learning statistical analysis of the dataset. The abundance of Arginase, Junction plakoglobin, Desmoplakin, Hexokinase-3 and Desmocollin-1 decreased, while that of BPI fold-containing family A member 2 increased in AIHp compared to HCs; the abundance of Gelsolin, CD14, Tumor-associated calcium signal transducer 2, Clusterin, Heterogeneous nuclear ribonucleoproteins A2/B1, Cofilin-1 and BPI fold-containing family B member 2 increased in PBCp compared to HCs. The abundance of Hornerin decreased in both AIHp and PBCp with respect to HCs and provided an area under the ROC curve of 0.939. Machine learning analysis confirmed the feasibility of the salivary proteome to discriminate groups of subjects based on AIH or PBC occurrence as previously suggested by our group. The topology-based functional enrichment analysis performed on these potential salivary biomarkers highlights an enrichment of terms mostly related to the immune system, but also with a strong involvement in liver fibrosis process and with antimicrobial activity

A top-down proteomic approach reveals a salivary protein profile able to classify Parkinson's disease with respect to Alzheimer's disease patients and to healthy controls

Parkinson's disease (PD) is a complex neurodegenerative disease with motor and non-motor symptoms. Diagnosis is complicated by lack of reliable biomarkers. To individuate peptides and/or proteins with diagnostic potential for early diagnosis, severity and discrimination from similar pathologies, the salivary proteome in 36 PD patients was investigated in comparison with 36 healthy controls (HC) and 35 Alzheimer's disease (AD) patients. A top-down platform based on HPLC-ESI-IT-MS allowed characterizing and quantifying intact peptides, small proteins and their PTMs (overall 51). The three groups showed significantly different protein profiles, PD showed the highest levels of cystatin SA and antileukoproteinase and the lowest of cystatin SN and some statherin proteoforms. HC exhibited the lowest abundance of thymosin &amp; beta;4, short S100A9, cystatin A, and dimeric cystatin B. AD patients showed the highest abundance of &amp; alpha;-defensins and short oxidized S100A9. Moreover, different proteoforms of the same protein, as S-cysteinylated and S-glutathionylated cystatin B, showed opposite trends in the two pathological groups. Statherin, cystatins SA and SN classified accurately PD from HC and AD subjects. &amp; alpha;-defensins, histatin 1, oxidized S100A9, and P-B fragments were the best classifying factors between PD and AD patients. Interestingly statherin and thymosin &amp; beta;4 correlated with defective olfactory functions in PD patients. All these outcomes highlighted implications of specific proteoforms involved in the innate-immune response and inflammation regulation at oral and systemic level, suggesting a possible panel of molecular and clinical markers suitable to recognize subjects affected by PD